Infective Endocarditis Associated With Intravenous Drug Use: Clinical Course, Biological Characteristics, and Outcomes of a Romanian Cohort

Abstract

Background Injection drug use is causing a wave of infective endocarditis (IE) worldwide, a severe and potentially deadly infection of the heart's endothelium. While this important public health problem has been well described in Western countries, available data from Eastern Europe are quite limited. Our study set out to describe this particular patient profile and its background, the clinical course of IE in this population, and evolution during and after hospitalization in a major infectious disease hospital in Bucharest, Romania. Methodology We reviewed the patient records of 57 people who inject drugs (PWID) admitted with IE between August 2019 and July 2025. Clinical, microbiological, and outcome data were collected and analyzed using standard descriptive statistics. Results The patients were mostly young men with a median age of 34 years. Most of these patients used heroin and other psychoactive substances and faced severe chronic co-infections: 63% were human immunodeficiency virus-positive, and 98% had hepatitis C. Most patients presented to the hospital with fever, malaise, and respiratory symptoms. Echocardiography confirmed valvular vegetations in over 90% of cases, most frequently on the tricuspid valve. Blood cultures were positive in 70%, most often revealing Staphylococcus aureus bacteriemia. More than half had embolic complications, 30% needed intensive care, and a quarter were candidates for cardiovascular surgery. The median hospital stay was 28 days, while mortality remained high at 17.5% during hospitalization and 35% at one year. Conclusions IE among PWID represents a life-threatening illness, particularly affecting young adults with multiple infections and comorbidities who are additionally burdened with social challenges. Despite prolonged hospitalizations and intensive care, their short- and long-term outcomes remain unfavorable.

Keywords: in-hospital mortality; infective endocarditis; injection drug use; people who inject drugs; staphylococcus aureus.

Figure 1. Flowchart showing the criteria of inclusion.

Duke-ISCVID= Duke-International Society for Cardiovascular Infectious Diseases; IE = infective endocarditis

Figure 2. Demographic distribution, housing stability, and drug use profile among PWID (N = 57).

(A) Sex distribution, showing a male sex predominance. (B) Proportion of participants without stable housing. (C) Age distribution histogram; the Gaussian curve shows normal distribution and a predominance of 30-35-year-old patients. (D) Frequency of reported use of major substances, showing a high prevalence of heroin and ethnobotanic use. PWID = people who inject drugs

Figure 3. Bar chart illustrating the prevalence of affected valves.

Figure 4. Pie chart describing the prevalence of IE with each identified pathogen.

IE = infective endocarditis; MRSA = methicillin-resistant Staphylococcus aureus; MSSA = methicillin-sensitive Staphylococcus aureus

Figure 5. Laboratory findings: significant pair-wise comparisons at admission versus discharge.

*: p < 0.05; **: p < 0.01; ***: p < 0.001. The Wilcoxon matched-pairs signed rank test was performed. A value of p < 0.05 is considered statistically significant. CRP = C-reactive protein